Process for hydrating lime.



PATENTBD OCT. 31, 1905.

I. RBANBY, JR. PROCESS FOR HYDRAIING LIME.

APILIOATIOH FILED JUNE 12,1905.

JAMES REANEY, JR, OF SHERWOOD, MARYLAND.

PROCESS FOR HYDRATING LIME.

Specification of Letters Patent.

Patented Oct. 31, 1905.

Application fil d June 12, 1905. Serial No, 264,809.

To all whom, it nuty concern.-

Be it known that I, J AMEs REANEY, J r., a citizen of the United States,residing at Sherwood, in the county of Baltimore and State of Maryland,have invented certain new and useful Improvements in Processes forHydrating Lime, of which the following is a specification.

My invention relates to a process for hydrating lime, and has for itsobject to provide a continuous process in which the difference ingravity between the lighter hydrated particles and the heavierunhydrated particles is availed of so as to retain the latter by reasonof their weight to complete their hydration, while the lighter hydratedparticles are permitted to escape.

It is a fact that after lime is moistened it begins to slake, and duringthis slaking operation itexpands and increases in bulk, but decreases inweight, and if while this change is taking place the mass is agitatedthe unhydrated particles, which are heavier than the hydrated particles,will gravitate to the bottom of the mass, while the lighter particles,which are hydrated, or partially so, will work toward the top of themass, where they may be removed, while theheavier unhydrated particlesare retained and further subjected to the hydrating process.

Thus my improved process consists in moistening the mass of quicklime,then agitating the mass to invoke the operation of gravity and cause theheavier unhydrated particles to settle to the bottom of the mass and thelighter hydrated or partially hydrated particles to rise to the surfaceof the mass, and to then permit the lighter hydrated particles toescape, but retain the unhydrated particles for further treatment.

The accompanying drawings illustrate a machine employed in carrying outthe process, in which- Figure 1 shows a longitudinal section through thecylinder of the machine. Fig. 2 illustrates a vertical cross-sectionthrough the same, and Fig. 3 shows a longitudinal section through aportion of a cylinder and illustrates a modified form ofinwardly-projecting flanges on the interior of the cylinder having theform of short spirals.

In carrying out the process I preferably employ a revolving inclinedcylinder 1, which is provided on its interior with a plurality ofinwardly-projecting flanges whichmay have the form of rings 2 or may besecured to the cylinder with the ends split and spaced apart to formshort spirals, as seen at 3. These flanges serve as abutments atintervals in the length of the cylinder and form compartments which actto retard the movement of the mass in passing from the higher toward thelower end of the cylinder. At the lower end the cylinder is providedwith acylindrical screen 4, which has its inner end 5 secured within thecylinder and its outer end 6 projecting beyond the lower end of thecylinder. This screen 4: is smaller in diameter than the cylinder 1, soas to provide an annular space 7 between it and the said cylinder. Thisspace also contains rings to impede the passage of the product; butthere is a space between these rings and the screen through which thesifted product can pass. A discharging-head is provided at the lower endof the cylinder and screen, and this head has two compartments 8 and 9.The compartment 8 receives the hydrated lime which discharges from theannular space 7 around the screen, while the compartment 9 receives allparticles of foreign matter that will not hydrate and which cannot passthrough the screen.

At the upper end the cylinder 1 is provided on the inner side with aplurality of flanged plates 10, which extend in a direction lengthwiseof the cylinder and serve to agitate and turn the mass over as it isreceived in the cylinder. A stationary plate or head 11 is also providedat the higher end of the cylinder, which closes the latter, and a chute12 is provided in said stationary head, and the entrance from the chuteto the interior of the cylinder is controlled by a swinging gate 13,having an arm 14 on the exterior of the chute.

Above the chute 12 is a liquid-tank l5, and a pipe 16 extends downwardlyfrom said tank and enters the cylinder 1. The lower end of this pipe isprovided with perforations 17, through which the liquid escaping fromthe tank may be sprayed within the cylinder. A chain or other connection18 is provided to connect the arm 14 of the gate with the valvemechanism of the tank, so that the opening of the gate to allow aquantity of lime to pass into the cylinder will cause the valve of thetank to be operated to discharge a given quantity of water into thehigher end of the cylinder. A steam-pipe 19 enters the lower end andextends through the cylinder toward the higher end, and said pipe isprovided with a plurality of perforations for. the escape of steam intothe cylinder.

1n carrying out the process the quicklime is placed in the chute inregular quantities and discharges therefrom into the higher end of therevolving cylinder. When the gate opens to allow'the quicklime to enterthe cylinder, the valve in the water-tank is operated so that a givenquantity of water is sprayed on the given quantity of quicklime. Vhilethe Water is thus sprayed on the lime the cylinder is revolved, and theflanged plates 10 agitate and turn the moistened lime over, so that theWater will be equally distributed over the lime. While this moisteningoperation takes place the lime is held in check by the first ring orflange 2, which serves as an abutment and also prevents the water fromflowing down the inclined cylinder and by thus retaining the waterinsures that the given quantity of lime will receive the predeterminedquantity of water. Thus in the first compartment the quicklime ismoistened by water and steam and as the cylinder revolves the smallerparticles will pass over the abutment or ring flange into the nextcompartment. 1n the second compartment the moistened lime begins toslake and as it slakes it swells and increases in bulk, but decreases inweight. In this operation some of the lime particles will undergo achemical change more quickly than others, and the result is that thoseparticles that are in a more advanced stage or condition towardhydration are lighter in weight than others, and the difference in theweight causes the lighter particles to rise to the surface of the mass du 1'- ing agitation of the latter, and as the second ring-flange servesas an abutment to retard the escape of the mass the latter will back upagainst this abutment with the heavier particles at the bottom and thelighter and more advanced particles will gradually work over the secondring-flange and escape into the third compartment. In this thirdcompartment further hydration will take place and the particles againseparate according to their weight, the lighter hydrated particlesworking to the surface of the mass and escaping over the abutment, whilethe heavier particles are retained and subjected to the action of thesteam until they change sufiiciently in weight to permit them to escape.The number of compart ments or flange-abutments may vary according tothe character or quality of the lime being treated. At the lower end ofthe cylinder the hydrated lime will pass over a revolving screen, whereit will be sifted to remove any foreign matter or unhydrated particlesthat may have passed through the machine and which cannot be hydrated,and the finer hydrated particles will sift through the screen,

when they may be further retained in the surrounding steam and separatedby the action of their different relative weights, thecompletely-hydrated particles escaping into the compartment 8 of thedischarging-head, While the particles or matter that cannot sift throughwill be discharged at the end of the screen into the compartment 9 ofsaid head. There may be one or more similar screens interposed of anymesh over Which the product can be made to pass before escaping from themachine, and thus be reduced to the fineness desired.

Having thus described my invention, What I claim as new, and desire tosecure by Letters Patent, is

1. The process of hydrating lime consisting of first moistening the massthen agitating the moistened mass to cause the heavier particles togravitate to the bottom and the lighter particles to rise to the surfaceof the mass and then removing the lighter particles from the surface ofthe mass.

2. The process of hydrating lime consisting of moistening the mass thenagitating the moistened mass to cause the heavier unhydrated particlesto settle to the bottom of the mass and the lighter hydrated particlesto rise to the surface and pass off while the heavier particles are heldin check.

3. The process of hydrating lime consisting of moistening the mass thenagitating the moistened mass to cause the heavier unhydrated particlesto settle to the bottom of the mass and the lighter hydrated particlesto rise to the surface and pass off while the heavier particles are heldin check and passing the separated hydrated particles over a screen.

4. The process of hydrating lime consisting of moistening the mass, thenagitating the moistened mass and holding it in check to cause theheavier particles to settle and the lighter particles to rise to thesurface of the mass, then removing the lighter particles from thesurface of the mass and again holding them in check while the agitationis continued to permit the heavier particles to settle and the lighterparticles to again rise to the surface from which they are removed.

5. Theprocess of lrvdratinglime consisting of moistening the mass, thenholding the mass in check while agitating it to cause the lighterparticles to rise to the surface and pass off then again holding theselatter particles in check while the agitation is continued to againenable the lighter particles to rise to the surface and pass off, thesesteps being conducted in a closed receptacle in the presence of steam.

6. The process of hydrating lime consisting of moistening the mass thenagitating the moistened mass to cause the heavier unhyd rated particlesto settle to the bottom of the mass and the lighter hydrated particlesto rise t0 the surface and pass off While the heavier I In testimonywhereofl aflix my signature in particles are held in check and passingthe presence of two Witnesses. separated hydrated particles over ascreen i and further retaining the separated particles in an atmosphereof steam until thoroughly hydrated and again separating by means oftheir varying specific gravities.

JAMES REANEY, JR.

Witnesses:

HOWARD D. ADAMS, JACOB FRANCE.

